Hydrogen-absorbing alloy electrode and process for producing the same

摘要

A first hydrogen-absorbing alloy electrode is obtained by applying a hydrogen-absorbing alloy powder on a collector or having a collector filled with a hydrogen-absorbing alloy powder and then sintering the hydrogen-absorbing alloy powder. The hydrogen-absorbing alloy powder is pre-pared by centrifugal spraying or gas atomizing and particles constituting the powder have a spherical shape, a nearly spherical shape, an egg-like shape or a mixed shape including the foregoing. The hydrogen-absorbing alloy electrode can readily be produced at low cost and have high packing density and good corrosion resistance, and can hence yield, when used for negative electrodes, metal hydride secondary batteries having excellent cycle characteristics. A second hydrogen-absorbing alloy electrode comprises a mixed powder containing a spherical-particle powder of a hydrogen-absorbing alloy and a powder as pulverized of the same alloy in a specific ratio. This electrode has high packing density and electronic conductivity, and can therefore gives batteries having excellent discharge characteristics on both high-rate discharge and low-rate discharge.